void main() {
  //String类型转换为Number parse()
  //Number类型转换为String toString()

  String str = "123";
  var myNum = int.parse(str);
  print(myNum);
  print(myNum is int);

  String price = "123.1";
  var money = double.parse(price);
  print(money);
  print(money is double);

  int b = 10;
  var str2 = b.toString();
  print(str2);
  print(str2 is String);


}
